The commit for 0e4e4318eaa5 increments QCOW2_OL_MAX_BITNR but does not
add an array entry for QCOW2_OL_BITMAP_DIRECTORY_BITNR to metadata_ol_names[].
As a result, an array dereference of metadata_ol_names[8] in
qcow2_pre_write_overlap_check() could result in a read outside of the array
bounds.
Fixes: 0e4e4318eaa5 ('qcow2: add overlap check for bitmap directory')
Cc: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Liam Merwick <liam.merw...@oracle.com>
Reviewed-by: Eric Blake <ebl...@redhat.com>
---
block/qcow2-refcount.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 3c539f02e5ec..46082aeac1d6 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -2719,15 +2719,17 @@ int qcow2_check_metadata_overlap(BlockDriverState *bs,
int ign, int64_t offset,
}
static const char *metadata_ol_names[] = {
- [QCOW2_OL_MAIN_HEADER_BITNR] = "qcow2_header",
- [QCOW2_OL_ACTIVE_L1_BITNR] = "active L1 table",
- [QCOW2_OL_ACTIVE_L2_BITNR] = "active L2 table",
- [QCOW2_OL_REFCOUNT_TABLE_BITNR] = "refcount table",
- [QCOW2_OL_REFCOUNT_BLOCK_BITNR] = "refcount block",
- [QCOW2_OL_SNAPSHOT_TABLE_BITNR] = "snapshot table",
- [QCOW2_OL_INACTIVE_L1_BITNR] = "inactive L1 table",
- [QCOW2_OL_INACTIVE_L2_BITNR] = "inactive L2 table",
+ [QCOW2_OL_MAIN_HEADER_BITNR] = "qcow2_header",
+ [QCOW2_OL_ACTIVE_L1_BITNR] = "active L1 table",
+ [QCOW2_OL_ACTIVE_L2_BITNR] = "active L2 table",
+ [QCOW2_OL_REFCOUNT_TABLE_BITNR] = "refcount table",
+ [QCOW2_OL_REFCOUNT_BLOCK_BITNR] = "refcount block",
+ [QCOW2_OL_SNAPSHOT_TABLE_BITNR] = "snapshot table",
+ [QCOW2_OL_INACTIVE_L1_BITNR] = "inactive L1 table",
+ [QCOW2_OL_INACTIVE_L2_BITNR] = "inactive L2 table",
+ [QCOW2_OL_BITMAP_DIRECTORY_BITNR] = "bitmap directory",
};
+QEMU_BUILD_BUG_ON(QCOW2_OL_MAX_BITNR != ARRAY_SIZE(metadata_ol_names));
/*
* First performs a check for metadata overlaps (through
--
1.8.3.1
